This invention relates to valves which are used to regulate the flow of gases, liquids, and/or loose materials through structures such as piping. More particularly, but not by way of limitation, this invention relates to valves which are used to control emissions into the atmosphere of the medium being regulated and transported.
Valves are used in a wide range of industries, ranging from nuclear facilities to oil and gas refineries. Generally, a valve will be used to regulate the flow of gases, liquids, or loose materials, or a combination thereof, through structures, such as piping, or through apertures by opening, closing, or obstructing ports or passageways. The various gases, liquids, or loose material being regulating may contain elements which are considered hazardous to the environment and humans.
Government agencies, on both a state and federal level, have begun to promulgate various regulations dealing with acceptable levels of emissions of hazardous gases, liquids or loose materials into the atmosphere. Valves, according to these new regulations, will contain seal means in order to prevent emission into the atmosphere of the materials being regulated. Valves containing actuator means, in order to remotely and/or automatically control operation of the valve, are particularly vulnerable to unexpected emission of the materials being transported because of the difficulty in creating a seal with the shaft of the actuator.
Therefore, there is a need in the industry for a valve which is controlled by a remote actuator that wi 1 provide a sealing means which will prevent the medium being transported from being discharged into the atmosphere. Thus, an object of this invention is a novel sealing means to effectively seal a moveable actuator shaft member.
Another object of the present invention is to have a back-up sealing chamber which will encapsulate the actuator shaft, and provide a secondary sealing means.